As this is one of the central functions of this file,
it deserves a proper documentation. This patch improves
the existing comment to format it as a kernel-doc style.
Signed-off-by: NEduardo Valentin <eduardo.valentin@ti.com>
Acked-by: NAmit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Update documentation for is_cpufreq_valid function so
that kernel-doc does not complain about return value.
Signed-off-by: NEduardo Valentin <eduardo.valentin@ti.com>
Acked-by: NAmit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

level will be used only if GET_FREQ mode is requested.
There is no potential harm with current code. But for
cleaning the compilation log, this patch initializes
level to zero.
Signed-off-by: NEduardo Valentin <eduardo.valentin@ti.com>
Acked-by: NAmit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Restrict the usage to GPL modules.
Signed-off-by: NEduardo Valentin <eduardo.valentin@ti.com>
Acked-by: NAmit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Simple fixes for making kernel_doc happy about
struct cpufreq_cooling_device. Includes also a minor
spelling fix.
Signed-off-by: NEduardo Valentin <eduardo.valentin@ti.com>
Acked-by: NAmit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Remove some unused header files.
Signed-off-by: NEduardo Valentin <eduardo.valentin@ti.com>
Acked-by: NAmit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

This code doesn't work on big endian systems because we're storing low
values in the high bits of the unsigned long.  It makes it a very high
value instead.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

- WARNING: Avoid CamelCase: <maskPtr>
Signed-off-by: NLaurent Navet <laurent.navet@gmail.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Signed-off-by: NZhang Rui <rui.zhang@intel.com>
Tested-by: NAmit Daniel kachhap <amit.daniel@samsung.com>

cpufreq cooling uses different frequencies as different cooling states.

But the per_cpu cpufreq_frequency_table may contain duplicate,
invalid entries, and it may be in either ascending or descending order.
And currently, code for parsing the per_cpu cpufreq_frequency_table
is used in several places and inconsistent.

Now introduce new code to
1. get the maximum cooling states
2. translate cooling state to cpu frequency
3. translate cpu frequency to cooling state
in one place,
with the correct logic of handling per_cpu cpufreq_frequency_table.
Signed-off-by: NZhang Rui <rui.zhang@intel.com>
Tested-by: NAmit Daniel kachhap <amit.daniel@samsung.com>

Convert to the much saner new idr interface.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

"level" parameter of get_cpu_frequency equals cooling state
of cpu cooling device, and it starts from 0.

Fix the misleading comment.
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

There are predefined cpu_masks that are const data structures.
This patch changes the cpu cooling register function so that
those const cpu_masks can be used, without compilation warnings.

include/linux/cpumask.h

 * The following particular system cpumasks and operations manage
 * possible, present, active and online cpus.
 *
 *     cpu_possible_mask- has bit 'cpu' set iff cpu is populatable
 *     cpu_present_mask - has bit 'cpu' set iff cpu is populated
 *     cpu_online_mask  - has bit 'cpu' set iff cpu available to scheduler
 *     cpu_active_mask  - has bit 'cpu' set iff cpu available to migration
 *
Signed-off-by: NEduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Silences the following sparse warning:

drivers/thermal/cpu_cooling.c:67:31: warning:
symbol 'notify_device' was not declared. Should it be static?
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

Problem of using this list is that the cpufreq_get_max_state callback will be
called when register cooling device by thermal_cooling_device_register, but
this list isn't ready at this moment. What's more, there is no need to maintain
such a list, we can get cpufreq_cooling_device instance by the private
thermal_cooling_device.devdata.
Signed-off-by: Nhongbo.zhang <hongbo.zhang@linaro.com>
Reviewed-by: NFrancesco Lavra <francescolavra.fl@gmail.com>
Reviewed-by: NAmit Daniel Kachhap <amit.kachhap@linaro.org>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

In the while loop for counting cpu frequencies, if table[i].frequency equals
CPUFREQ_ENTRY_INVALID, index i won't be increased, so this leads to an endless
loop, what's more the index i cannot be referred as cpu frequencies number if
there is CPUFREQ_ENTRY_INVALID case.
Signed-off-by: Nhongbo.zhang <hongbo.zhang@linaro.com>
Reviewed-by: NViresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: NAmit Daniel Kachhap <amit.kachhap@linaro.org>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

The curly bracket should be aligned with corresponding if else statements.
Signed-off-by: Nhongbo.zhang <hongbo.zhang@linaro.com>
Reviewed-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>

This patch fixes small bug on cpu_cooling. CPU cooling device has own
id generated with idr mathod. However in the previous version, it swapped
to all same id at last stage of probing as 0. This makes id's collision and
also occures error when it releases that id.
Signed-off-by: NJonghwa Lee <jonghwa3.lee@samsung.com>

This patchset introduces a new generic cooling device based on cpufreq
that can be used on non-ACPI platforms.  As a proof of concept, we have
drivers for the following platforms using this mechanism now:

 * Samsung Exynos (Exynos4 and Exynos5) in the current patchset.
 * Freescale i.MX (git://git.linaro.org/people/amitdanielk/linux.git imx6q_thermal)

There is a small change in cpufreq cooling registration APIs, so a minor
change is needed for Freescale platforms.

Brief Description:

1) The generic cooling devices code is placed inside driver/thermal/*
   as placing inside acpi folder will need un-necessary enabling of acpi
   code.  This code is architecture independent.

2) This patchset adds generic cpu cooling low level implementation
   through frequency clipping.  In future, other cpu related cooling
   devices may be added here.  An ACPI version of this already exists
   (drivers/acpi/processor_thermal.c) .But this will be useful for
   platforms like ARM using the generic thermal interface along with the
   generic cpu cooling devices.  The cooling device registration API's
   return cooling device pointers which can be easily binded with the
   thermal zone trip points.  The important APIs exposed are,

   a) struct thermal_cooling_device *cpufreq_cooling_register(
        struct cpumask *clip_cpus)
   b) void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)

3) Samsung exynos platform thermal implementation is done using the
   generic cpu cooling APIs and the new trip type.  The temperature sensor
   driver present in the hwmon folder(registered as hwmon driver) is moved
   to thermal folder and registered as a thermal driver.

A simple data/control flow diagrams is shown below,

Core Linux thermal <----->  Exynos thermal interface <----- Temperature Sensor
          |                             |
         \|/                            |
  Cpufreq cooling device <---------------

TODO:
*Will send the DT enablement patches later after the driver is merged.

This patch:

Add support for generic cpu thermal cooling low level implementations
using frequency scaling up/down based on the registration parameters.
Different cpu related cooling devices can be registered by the user and
the binding of these cooling devices to the corresponding trip points can
be easily done as the registration APIs return the cooling device pointer.
The user of these APIs are responsible for passing clipping frequency .
The drivers can also register to recieve notification about any cooling
action called.

[akpm@linux-foundation.org: fix comment layout]
Signed-off-by: NAmit Daniel Kachhap <amit.kachhap@linaro.org>
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: SangWook Ju <sw.ju@samsung.com>
Cc: Durgadoss <durgadoss.r@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Kyungmin Park <kmpark@infradead.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAmit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: NZhang Rui <rui.zhang@intel.com>